Typewriting machine



May 19, 1931. F. u. CONARD TYPEWRITING MACHINE Filed May 4, 1928 2 Sheets-Sheet 1 lnvenfor IE1 Illin- HIE May 19, 1931. F. u. CONARD TYPEWRITING MACHINE Fild May 4. 1928 2 Sheets-Sheet 2 Patented May 19, 1931 UNITED STATES PATENT OFFICE FREDERICK U. CONARD, OF IBRIDGEPORT, CONNECTICUT, ASSIGNOR T UNDERWOOD ELLIOTT FISHER COMPANY, OF NEW YORK,-N. 'Y., A CORPORATION OF DELAWARE ryrnwmrme MACHINE Application filed May 4, 1928. 'Serial No. 275,133:

ing mass abutting against rigidstops.

According to the invention, there is pro- Vided a double toggle-joint, that is, two as sociated or tandem toggle-j oints at each side of the machine, each Joint so arranged as to alternately flex or straighten out as the shiftframe moves from one case position into the other. operates the toggle-joints and is positively limited thereby, and there is absence of impact and noise, as will appear.

Springs cause the toggle-joints to alternately flex upon operation of theshift-key, so as to-insure against any of the togglejoints becoming locked in dead-center position.

The upper as well as the lower toggle joint may have provided asits stationary fulcrum an adjustable eccentric pivotwhich allows the extent of case-shift movement to be adjusted. The stationary pivots or .eccentrics may be placed upon special mountings or plates which are adj ustably mounted upon.

each side of the machine-frame. In adjusting the plates upwardly and downwardly Y upon the machine-frame, the stop-system as a whole is moved, so as to bring the printing line of the platen to proper vertical correla- 5 tion with the upper and lower characters respectively of the type-bar, which latter has an invariable printing height.

The silent motion stop is provided upon both sides of the machine, and may be con-' veniently incorporated in an Underwood portable-machine of the standard type, as well as in other machines. The toggle is automatically operated in a downward direction, by the combinediweights of the com- 3 ponent parts of the shift-frame. The up ward motion is governed by means which overcome saidweights and elevate the frame.

Other features and advantages will hereinafter appear. 4) In the accompanying drawings,

The movement of the shift-frame- Figure 1 is a longitudinal section through the main frame and the shift-frame, showing parts of the case-shift movement. The toggle-device is shown in lower case-shift posiion.

Figure 2 is similar to Figure 1, showing upper-case position of the shift-frame.

Figure 3 is a perspective view, according" to Figure-1, with parts of the main frame broken away.-

Figure 4; is an enlarged detail of the toggle-device, including the adjusting means thereon. I

Figure 5 is similar to Figure 4,-and shows the details of the toggle-device as drawn apart.

Figure6 shows digralmnatically the action of the springs upon the toggle-joints, indicating that, as one spring tends to buckle one pair of toggles, the other pair, although in end position, is still being held through spring tension slightly off dead-center position to insure against locking of the mechanism. The dead center is indicated by a light dotand-dash line. I

The Underwood portable typewriter includes a main frame 10, within which moves up and .down a U-shaped shift-frame or shifting track-frame, including a rear wall 11 and sides 12. Upon the shift-frame runs a carriage 13 upon which is mounted a platen 14. Type-bars- 15 strike the front of the platen. The carriage runs upon balls 16- connected by a rock-shaft 24 so as to form a shift lever 26 engaging upon a pin or pivot 27 of said arms 23.

Since fore and aft adjustment of the platen relative to the printing face of the type-bars is required in order to obtain correct typeimpressions, there is used an auxiliary plate 28 (see 'Figure 1) at each side of the machine, adj ustably mounted upon the inner side of the main frame and carrying the rear pivots of the links 22, and the rock-shaft supporting the'arms '23. Screw-and-slot connections 29 are shown between said plate 28 and the main frame, while an adjusting screw 30 at the rear idles within an ear 31 of the main" frame and may be operated to adjust the associated plate 28, and hence either end of the shift-frame may be adjusted forwardly or backwardly for truing the platen.

The silent stop-means for the key-shift movement according to the invention primarily consist of a double or tandem togglejoint at each side of the machine. One side includes an upper and a lower pair, 32 and 33, respectively, of toggle-links that can easilyhinge on pivot-studs 34. The togglejoints are opposed so that the meeting ends of the toggles-may be joined by a pivot-screw 39, which connects them to a forward extension 35 of said lower arm 23. The opposed ends of the tandem toggle-joints may be mounted by means of eccentric pivots 36 upon a plate orslidablemember 37, which in turn is itself upwardly and downwardly adjustable upon the main frame.

The member 37 may have'a longitudinal openin 38 to provide clearance for the movement 0 the pivot-screw 39, which carries said free inner ends of the toggle-j oints and which is secured by its nut 39. The proper extent of the shifting movement may be obtained by adjusting said eccentrics 36, while the proper range of the shifting movement as a whole relative to the fixed printing position of the types may be established by adjusting the,

plate 37 upwardly or downwardly. The plate 37 is formed to have angular terminals 40 to conveniently handle the same.

From Fi ures-4 and 5 it will be seen that the eccentric pivots 36, together with the plate 37, are held in vplace upon the main frame by screws 41 threaded into said eccentric pivots, and that, after loosening up upon those screws, all the necessary shifting movement adjustments may be performed.

The shift-key lever 26 is fulcrumed at 42 upon the main frame and is held in normalposition by a contractile spring 43' attached upon an ear 44 of the lever and anchored by a rigid pin 45 upon the main frame.

A depression of the shift-key 46' will cause the tail end 25 of the shift-key lever to engage the pin 27 and to raise the shift-frame to upper case-shift position (see Figure 2). The lower toggles arecaused to straighten out while concurrently the upper toggle.

joints are flexed, the proper flexing of the toggle-joints being insured through the tension of retracting spring 47. Each togglejoint has attached to one of its links one spring 47, which is anchored upon the machine-frame. The arrangement is such that the springs 47 will prevent the toggle-joint from entering a dead-center ali nment, so that the shift-frame is not locke in either upper or lower case-shift position. The weight of the carriage and shift-frame normally tends to straighten out the toggle 32, but pressure on key 46 relieves said weight, so that spring 47 may start the opening of the toggle, which is then collapsed as the shift-frame continues to rise.

The springs 47 alternately exert an increasingly retardant pull as the attached togglelinks approacfi dead-center alignment. Such retardant pul contributes to the quiet arrest of the shift-frame. Y

In providing the four springs 47, care is taken to have them of the proper and same approximate tension. This insures a counterbalancing effect as they pull one against the other- Such equalizing of pull insures ease in the operation of the toggle-joint units, and the shift-frame has no tendency to remain in upper-case position, nor is it hardto elevate play to counteract or offset the desired effects. In making such parts, the same or different metals may be used to'insure smooth easy working bearings.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I 1

claim:

1. In a typewriting machine having a main frame, the combination with a carriage, of a shifting mechanismtherefor including a carriage-track frame and means to reciprocate the same between lower and upper case position upon the main frame, an adjustable member secured at either side of the main frame, and silent stops pivoted to the members to limit the up and-down case-shift movement, said stops including toggle-connections -movably connecting: the shifting mass and the main frame in such a manner that upper and lower case positions are determined by respective dead-center positions of said toggle-connections.

properly adjusted and set as to leave no undue 2. In a typewriting machine having a main frame, the combination with a carriage, of a shifting mechanism therefor including acarriage-track frame and means to reciprocate the same between lower and upper case position upon the main frame, and silent stopmeans provided at either side of the machine to limit the up-and-down case-shift movement, said means at one side including a plate adjustably secured to the main frame, a pair of movable connections pivoted between the shifting mass and the plate, each connection collapsible from straightened to buckled position, said connections opposedly arranged so that the case-shift movement in either direction is limited as one connection straightens while the opposed connection buckles.

3. Ina typewriting machine having a main frame, the combination with a carriage, of a shifting mechanism therefor including a carriage-track frame and means to reciprocate v the same between lower and upper case pos1- tion upon the main frame, silent stop-means provided at either side of the machine to limit the up-and-down case-shift movement, said means at one side including a slidably adjustable member on the main frame, a pair of movable connections between the shifting mass and said member, each connection movable from a straightened to a buckled position, said connections opposedly arranged so that the case-shift movement in either direction is limited as one connection straightens while the opposed connection buckles, and means to control the movement of said connections.

4. In a typewriting machine having a main frame, the combination with acarriage, of a shifting mechanism therefor including a carriage-track frame and means to reciprocate the same between up er and lower case position upon the main rame, silent stop-means provided at either side of the machine to limit the up-and-down case-shift movement, said means at one side including a groove in the main frame, of movable connections between the shifting mass and the said bar, each connection collapsible from a straightened dead-center to a buckled position, said connections opposedly arranged so that the'case-shift movement in either direction is limited as one connection straightens while the opposed connection buckles, and spring-means to control the-buckling of said connections.

5. In a typewriting machine having a main frame, the combination with a carriage, of a shifting mechanism therefor including a catethe same between lower and upper case position upon the mainframe, silent stopmeans provided at either side of the machine to limit' the ,up-and-vdown case-shift movement, a rocking shaft device connecting said a bar adjustable therein, a paircarriage-track frame and means to recipro-' stop-means, said stop-means at one side inadjust said stop-means as a unitwitlrrefen.

ence to the main frame, each toggle-joint movable from a dead center to a buckled position, said toggle-joints opposedly arranged so that the case-shift movement in either direction is limited as one of the joints straightens while the opposed connection buckles, and spring-means between the buckling part of each connection and the main frame, said spring-means tending to buckle each connection and also effective to arrest the straightening' movement of the toggle-joints to prevent the same from entering true dead-center position.

6. In a typewriting machine having a main frame, the combination with a carriage, of

a shifting, mechanism therefor including a carriage-track frame and means to reciprocate the same between lower and upper case position upon the main frame, silent stopmeans provided at either side of the machine to limit up-and-down case-shift movement, said means at one side including a pair of movable connections between the shifting mass and the main frame, each connection'extending from a pivot upon the shifting mass to a stationary pivot upon the main frame and movable from a straightened to a buckled position, both connections opposed so that the case-shift movement in either direction is limited as one connection straightens while the opposed connection buckles, and means to adjust the two stationary pivots at either side upon the main frame simultaneously and to theisame extent.

7. In a typewriting machine having a main frame, the combination with a carriage, of a shifting mechanism 'thereforincluding a carriage-track frame and means to reciprocate the same between lower and upper case position upon the main frame,'silent stopmeans provided at either side of the machine to limit up-and-down case-shift movement, said means at one side including a pair of toggle-joints between the shifting mass and the main frame, each joint pivoted at one end upon the shifting mass and at the other end upon the main frame to be stationary thereon, said joints movable from a straightened to a buckled position, both connections opposedly arranged so that the case-shift movement in either direction is limited as one connection straightens while the opposed connection buckles, a mounting or plate to carry the two, stationary pivots, said plateadjustable up and down upon the main frame, and means to hold each stationary pivot in place upon the plate, which means are also effective tohold the plate upon the main frame.

8. In a typewriting machine having a main frame, the combination with a carriage, of

v .a shifting mechanism therefor including a case-shift movement, said means at one side including a. vertically adjustable member supported by the main frame, a pair of toggle-joints, each joint extending from a point upon theswing-frame to a stationary point upon said member, each joint also collapsible from a straightened-to a buckled position, said joints opposedly arranged so that the case-shift movement in either direction is limited as one joint straightens while the main frame, the combination with a. platen opposite joint buckles, and means to control the buckling of ,the joint.

9. In a typewriting machine haviiig a main frame, the combination with a.platen-supporting case-shift frame and means for reciprocatingsaid frame between-upper case and lower case position, of stops including an adjustable plate mounted on .the main frame, and tensile members secured to said plate and also to said shift-frame to limit the movements thereof in either direction.

10. In a typewriting machine having a main frame, the combination with a'platen and a supporting case-shift frame therefor, ofmeans for reciprocating said frame between uppercase and lower case position, stop-means to limit the shift-frame in its upward and downward movement, and means to move said stop-means as a unit to adjust the platen to the printing point.

11. In a typewriting machine having a main frame, the combination with aplaten and a supporting case-shift frame therefor, of means for reciprocating said frame between upper case and lowercase position,

tensile stop-means to limit the shift-frame in its upward and downward movement, and means upon which said stop-means are mounted, effective to move the latter as a unit to adjust the platen to the printing point.

12. In a typewriting machine having a main frame, the combination with a platen and a supporting case-shift frame therefor, of means for reciprocating said frame between upper case and lower case position, stop-means including toggle-mechanism to limit the shift-frame ,in its upward and downward movement, and means upon which said stop-means are adjustably mounted, to move the latter as a unit to adjust the platen to the rinting.point.-

13.: 1E1 a typewriting machine having a apd a supporting case-shift frametherefor, o tween upper case and lower case position,

means for reciprocating said frame be stop-means-to limit the shift-frame in its upward and downward movement including toggle mechanism having stationary pivots, and means, upon which said pivots areindividually adjustable, to move said stopmeans as a unit to adjust the platen to the printing point.

14. In a typewriting machine having a main frame, the combination with a platen, and a supporting case-shift frame therefor, of means for reciprocating said frame between upper pase and lower case position, stop-means, including toggle mechanism having stationary pivots, to limit the shiftframe in. its upward and downward movement, a plate upon which said pivots are in dividually adjustable and effective to move said stop-means as a unit to adjust the platen to the printing point, and means to secure said plate and the stationary pivots to the main frame.

FREDERICK U. OONARD. 

